Hi all,

 

I have a system very similar to Johnm's Atlas server. It has been working very well for several years. I am running Unraid v5b12a, with 4 disks plus parity and cache.

 

The disks in my array were almost full and I needed to add new new drive. Rather than adding another 2TB drive, I decided to replace the 2TB parity drive with a new WD Green 3TB drive, then reuse my old parity drive as a new data drive.

 

I stopped the array and shutdown, and added the new parity drive to the HBA controller.

 

After I started my server again, the Array was stopped and I was seeing a new drive. I changed the parity drive to select the new 3TB drive. I couldn't add the old parity at that time as drive 5 because unraid wouldn't allow me to until I had rebuilt the parity drive. I did that. Now I everything is working fine, except drive 5 has a red ball and shows "Not assigned". If I stop the array, the only option with drive 5 is "unassigned". Ie, I can't see the old parity drive showing up.

 

Not that after the parity drive was rebuilt, it did allow me to select the parity drive and add it to disk 5, and it allowed me to select the "Format" button to format the disk. But since then the disk has disappeared.

 

What am I doing wrong? How do I recover this disk, so I can add it to my arrange?

 

Thanks

Aaron

I don't understand what you did here:

Not that after the parity drive was rebuilt, it did allow me to select the parity drive and add it to disk 5, and it allowed me to select the "Format" button to format the disk. But since then the disk has disappeared.

Parity shouldn't need 'formatting'.

 

I don't mean to kick off a nasty discussion, but I'd try to go back to what was working.

If you still have the OLD 2 TB Parity drive around, I'd put it back in.

Reassign the old parity and cache drives if needed.

I'd run Parity Check to be sure data is safe.

Then I'd upgrade to v.5.0.5.

THEN, I'd do drive swaps.

 

From where you are currently at:

Attach a full syslog...just in case the cable to drive 5 got disconnected, or some such.

Was/is drive 5 your Cache drive?

 

http://lime-technology.com/wiki/index.php/Troubleshooting#Capturing_your_syslog

 

See the screenshot. He's not trying to format parity. His array is OK as it currently is since he has successfully rebuilt parity onto a new larger disk. What he wants to do now is use the old parity as a data disk in a new slot, but it is not available for assignment.

 

I don't know what the problem is but you might try removing it and rebooting without that disk. Then put it back in and see if it appears.

 

If that works, unRAID is going to want to clear the disk before it lets you format it, since a "new" disk must be all zeros in order to match existing parity.

 

Instead of assigning it and making unRAID clear it, you could consider preclear with the -n option. That will just zero the disk and write the preclear signature and skip pre-read and post-read. If you let unRAID clear it the array will be offline until it's finished clearing.

It sounds to me as though disk5 has dropped offline for some reason!  It is possible that when adding the new drive cabling to the existing drive was disturbed and has come loose?

 

Rebooting seems a good idea as then you can see if the drive is being seen at the BIOS level.  Also a syslog will help with determining what unRAID is seeing.

 

Regardless the idea of using pre_clear on the disk before adding it to the array seems a good idea to minimise array downtime.  It will also provide a confidence check of both the drive and its cabling.

trurl, you got it exactly right. Sorry if I wasn't clear.

 

Attached is a syslog. I can't read them really, but I do see the following block repeated frequently.

 

Mar 24 18:14:34 Tower kernel: mdcmd (1): import 0 8,80 2930266532 WDC_WD30EZRX-00D8PB0_WD-WMC4N1504230

Mar 24 18:14:34 Tower kernel: md: import disk0: [8,80] (sdf) WDC_WD30EZRX-00D8PB0_WD-WMC4N1504230 size: 2930266532

Mar 24 18:14:34 Tower kernel: mdcmd (2): import 1 8,64 1953514552 WDC_WD20EARS-00MVWB0_WD-WCAZA4560766

Mar 24 18:14:34 Tower kernel: md: import disk1: [8,64] (sde) WDC_WD20EARS-00MVWB0_WD-WCAZA4560766 size: 1953514552

Mar 24 18:14:34 Tower kernel: mdcmd (3): import 2 8,48 976762552 WDC_WD10EARS-00Y5B1_WD-WCAV56104077

Mar 24 18:14:34 Tower kernel: md: import disk2: [8,48] (sdd) WDC_WD10EARS-00Y5B1_WD-WCAV56104077 size: 976762552

Mar 24 18:14:34 Tower kernel: mdcmd (4): import 3 8,32 976762552 WDC_WD10EADS-00L5B1_WD-WCAU4D625148

Mar 24 18:14:34 Tower kernel: md: import disk3: [8,32] (sdc) WDC_WD10EADS-00L5B1_WD-WCAU4D625148 size: 976762552

Mar 24 18:14:34 Tower kernel: mdcmd (5): import 4 8,16 1953514552 WDC_WD20EARX-00PASB0_WD-WMAZA8442281

Mar 24 18:14:34 Tower kernel: md: import disk4: [8,16] (sdb) WDC_WD20EARX-00PASB0_WD-WMAZA8442281 size: 1953514552

Mar 24 18:14:34 Tower kernel: mdcmd (6): import 5 0,0

Mar 24 18:14:34 Tower kernel: md: disk5 removed

 

Does this suggest it can't read the disk at the bios level? The weird thing is that it does report the disk correctly as 2TB in the GUI.

 

It is probably a good idea to upgrade to latest stable, shutdown and check the cabling and confirm if the bios can see the disk. I'll try these things, but please let me know if you have any other suggestions.

syslog.txt

I upgraded to 5.05 and it worked fine, and the array came online fine. However I still can't assign disk 5.

 

I also notice I can access disk5 directly over a samba share, just can't assign it to the array. So assume the bios can see it.

 

I've had my Unraid Plus licence for a while. I see that on the Unraid website it lists that the Plus key supports 6 data disks. Is it possible this has changed, and my licence only supports 4 disks? Maybe I'm running into a licence limit? I do have a cache and parity drive. Is there a way to see the licence restrictions on my rig?

 

Thanks

I upgraded to 5.05 and it worked fine, and the array came online fine. However I still can't assign disk 5.

 

I also notice I can access disk5 directly over a samba share, just can't assign it to the array. So assume the bios can see it.

 

I've had my Unraid Plus licence for a while. I see that on the Unraid website it lists that the Plus key supports 6 data disks. Is it possible this has changed, and my licence only supports 4 disks? Maybe I'm running into a licence limit? I do have a cache and parity drive. Is there a way to see the licence restrictions on my rig?

 

Thanks

You can definitely have one parity, 5 data disks, and one cache drive with a plus license.

 

What doesn't make any sense is you say you can access disk 5 over samba. This sounds more like you already successfully added disk 5 to the array, shared it, and now it is showing as unassigned but you can still access it. You must be accessing the simulated drive 5. unRAID is able to show you the contents of the missing disk because it can reconstruct it from the parity and the other data disks.

 

You still need to go back to the BIOS and make sure the drive is seen by the hardware.

Ok, I will check. However I think I am accessing the disk directly using \\tower\disk5. As i understand it, this is accessing the drive directly, not going through the array.

 

I know today's plus licence can accommodate 5 data disks. But my licence is from 2011, and I thought the restrictions on number of disks may have been increased.

 

Note, there never was a disk 5 originally. Remember, this disk is my old parity disk which I have turned into a new data disk to increase the array size.

Ok, I will check. However I think I am accessing the disk directly using \\tower\disk5. As i understand it, this is accessing the drive directly, not going through the array.

 

I know today's plus licence can accommodate 5 data disks. But my licence is from 2011, and I thought the restrictions on number of disks may have been increased.

 

Note, there never was a disk 5 originally. Remember, this disk is my old parity disk which I have turned into a new data disk to increase the array size.

I do remember this is your old parity disk, but you also said that you formatted it. That was the part that I wasn't too sure about because you didn't say anything about unRAID clearing the drive. Did you preclear the drive before trying to add it? Or did unRAID take a few hours after you added it to clear it?

 

\\tower\disk5 would look the same whether it is simulated or not. Your syslog indicated it was missing, the webGUI says it is missing, all of your other drives look like they are spinning in your screenshot which would be necessary for unRAID to simulate drive 5.

 

All indications are that you have a missing disk in an array with parity and 5 data disks. You need to figure out why disk 5 is missing.

Ok, I will check. However I think I am accessing the disk directly using \\tower\disk5. As i understand it, this is accessing the drive directly, not going through the array.

 

If you're able to access the disk with \\tower]disk5 then it is part of the array and working just fine. 

 

By the way, if you did not clear the drive before adding it to the array, UnRAID will take several hours to clear it before it can format it and actually use the space ... but if you are indeed able to access it via \\tower\disk5 then that's all been done -- there may just be an error in the GUI display from your 3rd party GUI.    What does the stock Web GUI show?

Ok, I will check. However I think I am accessing the disk directly using \\tower\disk5. As i understand it, this is accessing the drive directly, not going through the array.

 

If you're able to access the disk with \\tower]disk5 then it is part of the array and working just fine. 

 

By the way, if you did not clear the drive before adding it to the array, UnRAID will take several hours to clear it before it can format it and actually use the space ... but if you are indeed able to access it via \\tower\disk5 then that's all been done -- there may just be an error in the GUI display from your 3rd party GUI.    What does the stock Web GUI show?

This wiki seems to describe the situation based on all the evidence we have so far in this thread. From that article:

 

Do not be misled by the fact that you can still read and write to the drive with a red ball indicator.

It does appear that disk5 was assigned correctly; but then red-balled due to a write error ... and is no longer being "seen."    But as noted above, you can still "access" it because of the fault-tolerant "magic" of UnRAID ... it's simply reconstructing it from the other drives in the array and parity.    Which means it clearly WAS assigned okay -- and has now been red-balled either because of a write error or simply because it's "missing"  (likely the latter).

 

Check your cables (both data and power) ... it's very likely one of them is not properly seated.

 

You were right. I shutdown my server, reseated the cables, and the disk appeared. I also reconfigured the disks and reassigned everything to get a grey ball on disk 5, then assigned that disk. cleared and formatted the disk and it is now working fine. Thanks all for your advice.

 

Just a bit of information for next time, all information that you added to the red-balled disk 5 was lost when you set a new configuration.  Setting a new config is almost never the correct thing to to when a disk red balls, normally you should rebuild from parity. Since you had just added and formatted the disk, I doubt that you lost anything, but for others reading, setting a new config guarantees data loss from the drive that red balled.

Ok, thanks for the info Jonathan. To clarify, I actually cleared configuration first because I wondered if this was a configuration issue from repurposing my old parity drive to be a data drive. It cleared the red ball, but didn't actually help the drive appear. So then I shutdown and reseated cables (which I should have done earlier following everyone's advice) and then it appeared. But definitately good advice.